ISSN 1070-4272, Russian Journal of Applied Chemistry, 2007, Vol. 80, No. 4, pp. 654 !659. + Pleiades Publishing, Ltd., 2007.
Original Russian Text + V.I. Chursin, 2007, published in Zhurnal Prikladnoi Khimii, 2007, Vol. 80, No. 4, pp. 670!675.
AND POLYMERIC MATERIALS
Features of Oxidative Degradation
of Hydroxyethyl Cellulose
V. I. Chursin
Research Institute of Leather-Shoe Industry, Joint-Stock Company, Moscow, Russia
Received October 30, 2006; in final form, December 2006
Abstract-The kinetics of degradation of hydroxyethyl cellulose in its oxidation with hydrogen peroxide,
sodium periodate, and potassium persulfate was studied. The effect of oxidation time and oxidant concen-
tration on the properties of the oxidation products was analyzed.
The stringent requirements to the environmental
safety of industries, including the leather-shoe indus-
try, make it necessary to reject some of the traditional-
ly used chemicals and processes. Therefore, one of
the main trends in the development of modern tech-
niques for treatment of leather raw materials is re-
placement of toxic chemicals with natural compounds
and, in particular, with plant tanning extracts, poly-
saccharides, and other nontoxic tanning compounds.
A promising approach to synthesis of environmen-
tally safe tanning agents from renewable plant raw
materials is based on oxidative transformation of poly-
saccharides into their dialdehyde derivatives .
The tanning capacity of starch dialdehyde prepared by
oxidation of starch with periodate was reported in .
It has been found, however, that polysaccharides (with
polygalacturonic acid as an example) are resistant to
oxidation at 20oC . Their oxidative degradation oc-
curs only in the presence of a catalyst or on heating
to 95oC . At the same time, it has been found 
that chitosan polysaccharide macromolecules are ox-
idized with hydrogen peroxide at 30oC and their mo-
lecular weight decreases in the course of oxidation
in proportion to the oxidant concentration. The pos-
sibility of oxidation of arabinogalactan with potassium
persulfate with the formation of carboxy groups was
reported in . No data have been reported on oxida-
tion of hydroxyethyl cellulose (HEC) with potassium
The aim of the study was to analyze the kinetics of
HEC oxidation and to obtain oxidation products with
a tanning capacity for collagen.
Hydroxyethyl cellulose (HEC) produced by the
Politsell Private Company [TU (Technical Specifica-
tions) 2231-013-32 957 739301] was used in our ex-
periments in the form of a 4% aqueous solution. Sod-
ium periodate, hydrogen peroxide (50%), and potas-
sium persulfate were used as oxidants. The optical
density of HEC solutions treated with sodium per-
iodate was measured on an SF-46 spectrophotometer
at a wavelength of 222 nm corresponding to the max-
imal absorption of periodate anions. The dynamic
viscosity of solutions was measured on a Brookfield
viscometer at a shear rate of 20 s
. The electrical
conductivity of solutions was measured on a Hanna
Instruments conductometer. The refractive index was
measured on a URL-1 refractometer.
The oxidation of HEC was studied in the dark at
room temperature. At regular intervals, an aliquot
of the reaction mixture was taken and its viscosity,
refractive index, and electrical conductivity were
measured. The carboxy group content of solutions of
oxidized HEC was determined by addition of aqueous
barium acetate (0.2 N), followed by titration of the
released acetic acid with NaOH (0.02 N). The spec-
troscopic characteristics of films prepared from oxi-
dized HEC were measured by Fourier spectroscopy.
The variation of characteristics of HEC solutions
in the course of oxidation is illustrated by Table 1.
These data show that, with the sodium periodate con-
centration increasing over 0.5 wt %, the oxidative
conversion of HEC sharply increases and viscosity